Abstract
Surgical patients can be comorbid and unfit, leading to worse patient outcomes and increased healthcare costs. The aim of this research explores the effects of high-intensity interval training (HIIT) on patient fitness (measured as VO2Peak) and clinical outcomes, and how to deliver this effectively. Methods included systematic reviews with meta-analysis, cohort studies including presurgical patients and those with obesity or heart conditions, qualitative interviews with presurgical participants after HIIT, and randomised clinical studies (RCT) in presurgical patients. An initial RCT showed that 12-14 sessions of preoperative HIIT significantly improved VO2Peak (2.35 mL·kg-1·min-1) and was associated with improvements in complications and length of stay. Subsequently, a meta-analysis, including these results, of preoperative HIIT of 832 patients in eight studies showed HIIT improved VO2Peak (MD[95%CI], 2.58 mL·kg-1·min-1 [1.52,3.65] P<0.001) and reduced postoperative complications (OR[95%CI], 0.47[0.34,0.67], P<0.001).
A prospective cohort study of 35 patients assessing the required dose of intense exercise for preoperative HIIT to be beneficial has shown that after 8 and 14 sessions respectively, 73% and 100% of the observed increase in VO2Peak is achieved, and that there is no significant improvement between 14 and 24 sessions. Ongoing work is assessing HIIT in obese patients (BMI>32.5kg) and those treated for heart failure. A current RCT compares standard care, HIIT at home with electronic supervision, and HIIT in hospital. Initial results suggest that HIIT at home and in the hospital are effective and qualitative assessment of patients' experiences suggest that preparation for surgery, and support from the research team were significant facilitators to adherence, while lack of time and pain were barriers. HIIT at home may mitigate cost and accessibility issues of HIIT in hospital.
These results suggest that HIIT should be included in preoperative care and should be tailored to address challenges in providing this service to patients with diverse demographics.